In 2009, a man from Leeds visited an eye specialist due to lingering sore eyes. The cause? His pet tarantula had shot tiny hairs at him, lodging in his cornea.

The 29-year-old was referred to an eye specialist by his GP due to eye troubles that had been bothering him for three weeks. Under magnification, tiny hair-like projections were found at varying depths in his cornea, some of which were slowly migrating deeper. The follicles were so small that even under microscope, and with micro-forceps, they were too tiny to remove.

What had happened? While cleaning the terrarium of his Chilean rose tarantula, the arachnid fired "a mist of hairs" that got lodged in his eyes and face. It turns out this is a common defense mechanism among New World tarantulas, as a way to ward of predators. Known as Urticating hair, the follicles are tiny, covered with multiple barbs, and can cause intense pain, as some species load them with irritating chemicals. The patient is fine now, thanks to intensive topical steroids.

I think we can come away from this with three lessons: 1) Nature is scary! 2) Always wear eye protection when dealing with giant hairy spiders. 3) Giant spider hair projectiles = equivalent of a bolt gun? B-movie makers, take note.